Garden Talk: April 28, 2005

From NGA Editors

Photo Contest

Gardening and photography enthusiasts, take note. The editors of NATURE'S BEST Photography magazine invite you to enter their First Annual NATURE'S BEST Backyards photography competition. More than $10,000 in cash and prizes will be awarded. All category winners and Highly Honored images will be published in a special edition of NATURE'S BEST Photography magazine and may be selected to appear in traveling photo exhibits related to the competition.

You may submit photos in any of the following categories: Wildlife, Plant Life, Water Life, Best Backyard, Before and After, Backyard Fun, Small Yard Spectaculars, Schoolyard Habitat, Gardening, and Against All Odds. There's also a special category for budding photographers 18 years old and younger.

The Sunniest Sundrops

Sundrops and evening primroses (Oenothera spp.) are popular perennial flowers that are easy to grow in most parts of the country. While there are more than 120 species available, only a handful are typically grown as garden plants. The saucer-shaped, bright yellow or pink flowers are a common sight in early summer, blooming for three to four weeks.

From 1998 to 2003 the Chicago Botanic Garden (USDA zone 5) evaluated 19 different species of Oenothera for characteristics such as flowering display, disease and pest resistance, cultural adaptability to climate and soil, and winter hardiness. While 16 of the species survived the trial period, there was a significant difference in flowering performance. Most of the species had only sparse blooms, but the evening primrose Oenothera speciosa 'Siskiyou' (pink flowers) and the sundrops O. fruticosa 'Fyrverkeri' (yellow flowers) had impressive numbers of flowers -- up to 100 percent flower coverage -- over the same period. They also showed healthy growth and winter survival.

New Safer, Systemic Fungicide

Diseases such as sudden oak death (SAD), black spot, scab, bacterial blight, and fire blight are the scourge of many trees, shrubs, fruits, and vegetables. To control these diseases home gardeners have had to resort to growing resistant varieties (if available), using cultural techniques such as crop rotation, or spraying toxic chemicals.

Now a new, low-toxicity, systemic fungicide is available that features potassium salts of phosphoric acid as the active ingredient. Agri-Fos fungicide has been used successfully in Australia and is now available in the United States. Although not considered organic, its low toxicity allows gardeners to reenter their fields only 4 hours after applying the fungicide, and there are no harvesting restrictions. It can be used on bedding plants, ornamentals, citrus, apples, pears, grapes, strawberries, and a variety of other fruits and vegetables.

The phosphate-based fungicide is quickly absorbed into plant cells and spread throughout the plant, so it kills disease organisms on contact. It also boosts the plants natural defenses to attack and stimulates the plant to tolerate higher levels of environmental stress.

Grounds for Gardens Perk Up Your Plants

If you're looking for a high-nitrogen soil amendment, attractive mulch for acid-loving plants, or deliciously fragrant addition for your compost heap, seek no further than your neighborhood Starbucks. The coffee chain is now offering bags of used grounds sporting colorful Grounds for Gardens labels free to green-thumbed patrons at their cafes. Grounds for Gardens are comprised of very fine espresso grounds and do not include filters so they're easy to work with. Here's how to use them to best advantage in your horticultural pursuits.

As a mulch for shrubs, trees, and roses. Spread grounds 1 to 2 inches deep. More is not better: A deep layer can keep water from penetrating the soil.

As a plant nutrient source. Coffee grounds contain an NPK analysis of 2-0.3-0.2. Mix them thoroughly with soil or potting mix, so the grounds comprise no more than 25 percent of the total soil volume.

As a compost additive. Mix grounds thoroughly with other organic materials. For best results, grounds should comprise no more than a quarter of the total volume.

As feed for redworms in a compost bin. Mix the grounds with other food scraps or bedding to prevent grounds from caking within the worm bin.

If there's not a Starbucks near you, check with the manager of the corner diner or even the local gas station to see if they'll save up their coffee grounds for you. If your primary goal is to add them to your compost or feed them to your worms, paper filters are no hindrance - worms and microbes will welcome the carbon they supply.